Transmission line connector



June 12, 1962 H. G. KOENIG 3,039,074

TRANSMISSION LINE CONNECTOR Filed Nov. 2, 1959 Wig l 7z lnml Patented June 12, 1962 "lice 3,039,074 TRANSMISSIGN LINE CONNECTOR Herbert G. Koenig, Griggsville, ill, assignor to Trio Manufacturing Co., Griggsville, Ill., a corporation of Illinois Filed Nov. 2, 1959, Ser. No. 850,220 2 Claims. (Cl. 339-99) This invention relates generally to connectors for transmission lines and more particularly is concerned with a connector which is adapted to enable the trans-' mission line from an antenna to be connected to a receiver. l

The connection of transmission lines to receivers is achieved normally by providing a pair of screw terminals on the rear of the receiver, forming a looped end on each of the transmission line conductors, and securing the looped ends under the screw terminals. In the case of high frequency receivers, such as for example, television receivers, where the transmission line must have a proper signal transmitting characteristic, present a proper impedance to the antenna input and present a proper impedance to the receiver input, the line normally is formed of a pair of spaced conductors embedded in a flexible insulating material. Such line has by custom been fairly well standardizedboth as to dimensions and impedance.

This application is a continuation-in-part of a co-pending application Serial No. 763,985, filed September 29, 1958, and entitled, Transmission Line Connector, now Patent Number 2,997,683 issued August 21, 1961.

In said co-pending application, there is described a transmission line connector which is primarily intended to be permanently associated with the antenna. The end of the transmission line at the antenna is inserted into a suitable base and a thumbscrew is tightened, bringing a pair of diagonally disposed pronged or tined members against the transmission line. Each of the tined members bites into the insulation along one of the opposite edges of the transmission line, establishes electrical contact with the transmission line, and is connected to one of the input terminals of the antenna. In this manner it becomes unnecessary to cut away any of the insulation on the transmission line, the connection is positively and immediately made without the need of stripping tools or screw drivers or the like, and further, the connection established, being buried in the insulation, isless subject to corrosion than one which is normally exposed.

This invention has objects which are common with the objects or" the said co-pending application, such as the provision of a structure which will enable a transmission line to be connected to a pair of terminals by turning a thumb screw and without requiring the insulation to be stripped from the line, the provision of a simple, economical and rugged device for accomplishing these and other purposes.

In addition, this invention has other objects. In the case of a receiver it is often desirable to qiuckly separate the transmission line from the receiver. Nevertheless it is required that the connection with the receiver terminals be positive and not readily disturbed. The invention herein provides a connector having these qualities. Another problem arises by virtue of the fact that the screw terminals of all receivers are not uniformly spaced apart. The invention herein provides means for adjusting the spacing between the spade lugs carried by the connector to enable ready secur-ement of said connector with practically any television receiver terminals.

Other objects will appear as the description of the invention embodied in a preferred practical structure is set forth hereinafter. An important aspect of the invention, as in the case of the invention of the co-pending application, is that all of the functions which the device is capable of performing are achieved with maximum electrical efficiency, but with a structure that has a minimum of simple parts easily and quickly assembled so that the device is extremely economical and thus available to a wide cross section of consumers.

In the drawings:

FIG. 1 is a perspective view of the rear of a television receiving set having the connector of the invention attached to the antenna terminals thereof, and with a transmission line connected thereto.

FIG. 2 is a side elevational view of the connector, showing the same separated into its two parts to illustrate the manner in which the transmission line is readily disconnected from the receiver.

PEG. 3 is a sectional view through the connector taken generally along the line 3-3 of FIG. 2 and in the direction indicated.

FIG. 4 is a sectional view through the assembled connector taken generally along the line 4-4 of FIG. 3 and in the direction indicated, the two parts having been brought together for this view.

FIG. 5 is a plan view of the assembled connector taken from the top of the same.

FIG. 6 is a plan view of the portion of the base of the connector which is secured to the screw terminals of the television receiver.

FIG. 7 is a plan view of a section of transmission line showing the lines of punctures caused by the teeth of the connector.

FIG. 8 is a bottom plan view of the block showing the grooves provided therein, and illustrating diagrammatically the manner in which the transmission line is laid therein and engaged by the toothed contact members.

The transmission line connector embodying the invention is designated generally by the reference character 10 and the same is adapted to be employed in removably connecting a two-wire transmission line 12 such as conventional 300 ohm television lead-in Wire to a television receiver 14 or the like. The receiver 14 is of conventional construction, and the transmission line 12 is normally connected across a high frequency tuned circuit to ground whereby there are two terminals presented to the exterior of the receiver. A typical arrangement is shown in which there is a low leakage terminal strip 16 of some good insulating material mounted on the rear of the receiver 14, having the screws 18 threaded therein to serve as the electrical terminals. The ordinary manner of connecting the transmission line 12 t the screw terminals 18 in the past has usually been to strip the wires 20 back a sufficient distance by cutting away the insulation 22 until there are two lengths of wire protruding which can be bent into loops and then engaging the loops to the screw terminals 18. Of course, this is crude, and hardly satisfactory, because in moving the receiver or disconnecting the transmission line, a screw-driver was required, the connections would not be positively made, the stripping may have weakened the core, and breakage would occur, etc.

In accordance with this invention, the connector 10 not only provides positive electrical connection with the transmission line without the need for stripping, but also provides an instantly disengageable connection with the receiver.

The connector 10 is formed of two parts, a base 21 which is adapted to be attached to the receiver terminals 18, and a shell 23 which is adapted to be secured to the transmission line 12. The two parts or sections are normally engaged with one another by means of a plug-in connection comprising a pair of male prongs 24 carried on the shell 23, and a pair of sockets 26 provided in the base 21. Electrical connection is established through the respective parts from the prongs and sockets to the transmission line and the receiver terminals, so that when the parts are assembled, electrical connections are from the conductors to the respective screw terminals 18. The prongs and sockets may be in opposite parts than those illustrated, and may be keyed, if desired.

Each of the base and shell is formed of a molded insulating material such as thermo-setting or thermoplastic resin, ceramic or the like, and although not essential, the general cross section of both is rectangular to give a complementary appearance when assembled.

The base or platform 21 is preferably hollow, since the strength and insulative properties are in no way impaired, and the weight and amount of materials are thereby reduced. The surface 27 facing the shell 23 is flat, so as to enable face-to-face engagement with the bottom surface 28 of the shell 23. This latter surface is also fiat although it may be grooved or ribbed. On its opposite face the base 21 is provided with U-shaped recesses 30 formed by suitable molded walls and in each recess, spaced below the plane of the surface 33 is a large spade lug 32 having an end 34 extending beyond the side edge of the base, each end 34 being provided with an open ended slot 36 to enable facile securement of the lug 32 to the screw terminals 18. Each end is disposed in a plane which is parallel to and spaced from the plane of the surface 31 by means of an integral offset bend 38 formed in each lug 32. When the spade lugs 32 are secured in place, the entire base 21 will be standing off, that is, spaced from the rear Wall of the receiver 14-. Each lug 32 is pivotally secured to the base 21 by means of a metal rivet 4d the head of which is recessed in surface 27. In this manner, each of the lugs 32 is capable of limited pivotal movement to enable the distance between the slots 36 to be adjusted for different distances between screw terminals 13. This is shown in broken lines in FIG. 6.

A metallic spring contact finger 42 is engaged by the head of each rivet 4%, as for example by forming an eye or the like on the end of the finger 42, and there is an extension 44 of each finger disposed in the respective sockets 26 to be wiped by the prongs 24 when inserted thereby establishing electrical contact therewith.

The shell 23 has a central passageway 46 which is rectangular in cross section and which is defined by lateral side walls 48 and S0. The passageway 46 is closed off at 52, at what may be termed the outer end thereof, since that end is furthest from the base 21 when the shell is assembled to said base. An actuator 54 is mounted in the closed off end 52, said actuator comprising a thumb screw, the head 56 of which is exterior of the shell 23, and the threaded shank 58 of which is disposed in the center of the passageway 46. A nut 63 is molded into the end 52 and the shank 58 is threaded therethrough. A block 62 of insultaing material is slidably disposed in the passageway and has a socket 64 for seating the end of the shank 53. The opposite surface of the block is suitably grooved as will be explained.

The lateral walls 48 are imperforate and extend as a kind of spacer between the walls 50. These latter walls are wider at their left hand ends, as viewed in FEGS. 3 and 5, giving the walls a somewhat wedge-like shape. This gives the shell bottom (left hand end) a rectangular configuration, and the bottom ends of the flared portions of the walls are connected by webs 66. The bottom end of the passageway 46 is closed off by means of a rectangular plate 68 which is secured across the webs 66 by means of metal rivets 76 which are best seen in FIG. 3. Sandwiched between the secured plate 68 and the webs 66 are a pair of metal contact plates 72 each of which has a right angle bent portion 74 that extends into the passageway 46. The bent portions 74 are parallel one to the other but are oblique relative to the walls forming the passageway 46 so that when the teeth formed on the ends of the bent portions 74 bite into the insulation 22 of the transmission line 12, the resulting perforations will have the appearance of FIG. 7. The face of the block 62 opposite that having the socket 64 is grooved to receive these teeth and is also provided with a track within which the transmission line 12 is laid. The grooves for the teeth are deeper than the track so that they will pierce the transmission line when forced against the same by the block 62.

In FIG. 8 there is illustrated a bottom plan view of the block 62. The block has a track formed therein which is designated 76, the width thereof being the width of the conventional 300 ohm transmission line 12. The line is inserted through suitable openings 7 8 formed in the walls 5% and is laid in the track 76. The depress-ion of the track forms upstanding side flanges 8t and there is a center groove 8-2 which is deeper than the track 76. Two grooves 84 are formed in the block which extend across the flanges and the track 76, having a depth substantially equal to that of the center groove 82. The right angle bent portions 74, as previously mentioned, have sharp teeth formed on the edges thereof, and these teeth, designated 86 are intended to bite into the transmission line. The portions 74 are aligned with the grooves 86 so that as the block 62 is driven down the passageway 46 by the actuator 54, with the transmission line 12 in place, the teeth will readily pierce the insulation 22 and metallically grip the conductors 26, each portion 74 thus engaging one of the respective conductors and establishing electrical contact therewith.

The members 72 may be keyed in position against movement by suitable pins or projections (not shown) between the plate 68 and webs 66. The prongs 24 have heads which are engaged by the members 72 to complete the electrical connections to said prongs.

The manner in which the apparatus is used is believed obvious from the above description, and reference may be had to the copending application for constructional details of the shell in addition to those given here.

What it is desired to secure by Letters Patent is:

l. A connector device for electrically connecting the conductors of a transmission line, having two spaced conductors embedded in insulating material, tothe screw terminals of a receiver with said screw terminals having an indeterminate spatial relationship to each other, said connector device comprising, a shell member having means defining a passageway, a slideable block disposed in said passageway, means exterior of said passageway for actuating said block, a pair of toothed contact means disposed in said passageway, and side openings provided in said shell to enable the insertion of said transmission line between said block and contact means whereby the insulation of the transmission line is pierced by the contact means to establish electrical connection between the contact means and the respective conductors embedded Within the transmission line, a pair of spaced apart rigid projections in electrically conductive relation to said contact means and extending outward from the shell, a base member adapted to be mounted on said shell, a pair of socket portions formed in said base member and adapted to receive said rigid projections therein, said base member having a pa r of matched recesses formed therein on the side thereof opposite the said shell member and offset from said socket portions, a pair of spaced lug members mounted for pivotal movement within said respective recesses, each of said lug members having free ends extending in the same general direction and having an offset portion perpendicular thereto and that portion is adapted to engage the screw terminals at any one of the indeterminate spatial relationships assumed thereby, electrically conductive mounting means for so swingably mounting said spaced lug members within said recess so that only the perpendicular off-set portion thereof extends outward from said recess, electrically conductive strip connector means disposed partially within said socket portions, the portion disposed within said socket portions adapted to form a resilient connection to a respective one of said rigid projections, the other portion thereof connected to said mounting means whereby to maintain in electrical circuit relationship the elements comprising the screw-tenninals, the lug members, the mounting means, the strip conductor members, the rigid projections, the contact means, and the conductors of the transmission line thereby to form an instantaneously separable electrical connection between a receiver and an exterior transmission line without the separation of the said exterior transmission line from said contact means.

2. In a device for achieving an electrical connection between an exterior transmission line leading from an antenna and having a pair of conductive elements embedded therein, and a television receiver having a pair of exterior screw terminals thereon wherein said pair of exterior screw terminals may be disposed in an indeterminate spatial relationship one to the other: the device comprising, an instantaneously separable pair of connector bodies including a base member adapted to be removably secured to said screw terminals and a shell member adapted to have said transmission line secured therein without the need for stripping off the insulation therefrom; electrically conductive cooperative means having an instantly separable junction, said cooperative means comprising first means on said base member and second means on said shell member, said first means comprising a pair of spaced pivotally mounted lug members having free ends extending in the same general direction from said base member, a pair of socket portions offset from said lug members and opening oppositely thereto, and electrically conductive strip means, a portion of which is disposed within a respective socket portion, and a portion thereof making electrical connection with said pivotally mounted lug members, and said second means comprising a pair of electrically conductive projections extending from said shell portion and adapted to be received within said socket portions of said first means to form said instantaneously separable junction, toothed contact means adapted to pierce said transmission line whereby to make electrical connection with the conductors embedded therein, and electrically conductive means connecting said projections with said toothed contact means, and said shell further including a passageway formed therein and having said toothed contact means therein, a slideably movable block member rideable within said passageway of said shell, and means for actuating said block member with the transmission line insertable be tween said block member and said toothed contact means whereby said transmission line is pierced by said toothed contact means to establish electrical connection to said rigid projections, to permit said electrical connection to be established between said receiver and said transmission line when said separable junction is connected.

References Cited in the file of this patent UNITED STATES PATENTS 331,042 De Mier Nov. 24, 1885 1,986,269 Jermain Jan. 1, 1935 2,254,914 Rugg Sept. 2, 1941 2,399,408 Walk Apr. 30, 1946 2,566,425 Paine et a1. Sept. 4, 1951 2,627,537 Weisberg Feb. 3, 1953 2,740,100 Broverman Mar. 27, 1956 2,832,057 Thorson Apr. 22, 1958 2,929,043 Phillips Mar. 15, 1960 FOREIGN PATENTS 612,971 France Aug. 10, 1926 

